Exploring ideas for the above. Have others run such a campaign using TW2000? I would love to discuss possible scenarios, adventures, NPCs and other situations with similar fans of this genre. I am also going to be posting some of my own ideas here and welcome feedback and ideas.

My campaign is set in and around LA. The group consists of a university profesor, a special forces officer, an intelligence officer, a police officer, and a professional burglar.

I prefer the idea of some kind of infected crisis. A friend of mine helped me put this idea together. I realize the science is a bit wonky but the important thing is that it sound good--and none of my players took bio beyond one level in high school anyway.

The S1R1 virus Syptoms

The S1R1 is a highly infectious disease spreading like influenza and able to survive on surfaces for up to 24 hours. Infected individuals do sneeze often with infected droplets of S1R1 able to spread up to 6 meters. One infected individuals on average infected 5 other people and it has a mortality rate of 86% (in other words in a sample of 100 people, 86 people who contracted the virus died within 8 days, anybody who lived longer then 8 days underwent euthanasia, 10 out of the 100 who contracted the virus did not

These symptoms kick in by day 2-4
Dilerium
Dementia
Amnesia
Muscle cramps and spasms

The onset of early dementia occurs as the virus travels up the spinal column disrupting higher brain functions. These symptoms can occur from day three of infection to day six.

The victim may wander around like a 'zombie' and be largely confused by what happens around them. It is difficult for them to rest due to the discomfort and they may wander until they collapse from exhaustion. They are largely dangerous as passive carriers, as their bodily fluids are highly contagious.

Later symptoms become apparent after day 5
Psychosis
Violent behavior
Hallucinations
Uncontrollable
By day eight the victim is a shell of their former self, unable to see reason and lashing out at any nearby person.

These infected can be dangerous, but mostly if bothered. However there is a risk that they will act like 'slow zombies'. They are capable of moving quickly at this stage but are mostly wandering in a world of madness. They still get hungry and thirsty. They are particularly dangerous to weak, injured or other poorly defended people. In crowds they can be very dangerous. They rarely attack one another but may do so.

Feral Infected State
Have heightened levels of adrenaline, the brain swells and becomes inflamed leading to massive chemical imbalances leaving a late infected, extremely violent and suffering frequent muscle spasms and sometimes seizures. Their brain retreats into a type of "Primitive state" where they rage after anything that moves like "prey" and grabs their attention.

If you want more control over the scenario, have the group trying to infiltrate a fenced in "Research Facility" to get to the "cure" before things get out of hand. In this scenario, the infection hasn't spread beyond the facility and the characters may know NOTHING about the agent/virus in question. Since the "environment" is much smaller, it is that much easier for you to control the story's "pacing" as well as the characters' movement. If you liked the scenario, let the virus "escape" the compound. The players are now at "Ground Zero" for a global pandemic.

If you want more control over the scenario, have the group trying to infiltrate a fenced in "Research Facility" to get to the "cure" before things get out of hand. In this scenario, the infection hasn't spread beyond the facility and the characters may know NOTHING about the agent/virus in question. Since the "environment" is much smaller, it is that much easier for you to control the story's "pacing" as well as the characters' movement. If you liked the scenario, let the virus "escape" the compound. The players are now at "Ground Zero" for a global pandemic.

I think that's a good one. As you say it's more of a sandbox. Also it allows for a precise map of an area, insertion and extraction, thta sort of thing.

The idea of running zombie scenarios is why I asked a while back about rules for called shots (particularly head shots), since some versions can only be taken down that way.

There's a pretty good Dark Osprey book about zombies by Joseph A. McCullough, who's also a short story author and game designer. It discusses different types of zombies from the perspective of a historical journalist in a zombie-infested world.

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Writer at The Vespers War - World War I equipment for v2.2

The idea of running zombie scenarios is why I asked a while back about rules for called shots (particularly head shots), since some versions can only be taken down that way.

There's a pretty good Dark Osprey book about zombies by Joseph A. McCullough, who's also a short story author and game designer. It discusses different types of zombies from the perspective of a historical journalist in a zombie-infested world.

I've read that one. My choice would be to eat a bullet- two if possible.

What I'm mostly adopting from Crossed is that there are more impulses than just eat and kill. Basically my infected become rabid beasts, with rudiments of human intelligence. Perhaps somewhat like the creatures from Omega Man/I am Legend. Essentially, they are hostile to non-infected--no one yet knows why--and see animals and other humans as prey, generally. However they may also have the urge to mate, and they may appear cruel and sadistic, but this is less the creative mad cruelty of the Crossed and more that they have no inhbitions. Nearly all lack the ability to use anything more than the most basic technology rather in the manner of an ape or monkey. That is, they might bash at you with a baseball but but it's only because they had it on hand.

Also like the Crossed, I wanted them to be capable of eating, drinking and resting, otherwise, as I see it, the plague, since it crashes and burns so quickly, would end in a matter of days.

I've read that one. My choice would be to eat a bullet- two if possible.

What I'm mostly adopting from Crossed is that there are more impulses than just eat and kill. Basically my infected become rabid beasts, with rudiments of human intelligence. Perhaps somewhat like the creatures from Omega Man/I am Legend. Essentially, they are hostile to non-infected--no one yet knows why--and see animals and other humans as prey, generally. However they may also have the urge to mate, and they may appear cruel and sadistic, but this is less the creative mad cruelty of the Crossed and more that they have no inhbitions. Nearly all lack the ability to use anything more than the most basic technology rather in the manner of an ape or monkey. That is, they might bash at you with a baseball but but it's only because they had it on hand.

Also like the Crossed, I wanted them to be capable of eating, drinking and resting, otherwise, as I see it, the plague, since it crashes and burns so quickly, would end in a matter of days.